Method of locating leaks and repairing well tubing in situ



G. L. LOOMIS July 13, 1965 METHOD OF LOCATING LEAKS AND REPAIRING WELLTUBING IN SITU 4 Sheets-Sheet 3 Original Filed July 2 1962 a @i z WM//////////l/lr/l/ fl, t

INVENTOR Gza/wv L A oa/ws BYW 09 United States Patent ice 3 194,310METHOD OF LOCATH IG LEAKS AND REPAIRING WELL TUBING IN SITU Glenn L.Loomis, Pasadena, Tex.; Jean Doyle Loomis, independent executrix ofGlenn L. Loomis, deceased, assignor to Jean Doyle Loomis, individuallOriginal application July 2, 1962, Ser. No. 206,631. Divided and thisapplication Mar. 6, 1964, Ser. No. 358,393

3 Claims. (Cl. 166-4) This application is a division of my copendingapplication, Serial No. 206,631, filed July 2, 1962, and is entitled tothe filing date thereof.

The present invention relates to an improved method for testing welltubing or pipe for leaks and repairing any leaks located. Morespecifically, the present invention relates to testing well pipe in awell to locate leaks and then repairing the well pipe in situ.

Present day gas and oil wells are completed by a procedure of cementingthe final production tubing string into the well bore. This completionpractice is usually done in order to eliminate additional expense ofprimary strings of casing, production packers and the like.

While the practice of cementing the final production tubing into thewell bore has the advantage of being more economical, there is also thedisadvantage that the tubing cannot be easily pulled for repairs shouldleaks develop either in the threaded joints of the connecting collars orin the tubing wall. Oftentimes, leaks develop long after the intialcompletion of the well and while the well is in use. Uncontrollablefactors such as corrosion of the tubing or vibration of the same causesuch leaks and, heretofore, there has been no satisfactory way to locateand repair the leaks without pulling the tubing out of the well hole andreplacing the defective well pipe and/ or threaded collars. Even inwells where the flow tubing or pipe may be easily removed to test forleaks and repair of the same, such procedure oftentimes results infurther leaks developing in the joints when the string is lowered againinto the well. This results in loss of operating time as the string mustagain be removed and repaired.

Efiorts have been made to apply sealants to leaks located in well pipeby pumping the sealant down the well pipe to the area of the leak. Sincethe sealants include a plastic sealant material which must be mixed witha catalyst, the mixing of the plastic sealant material with the catalystat the surface has proved an unsatisfactory operation as the catalyticaction oftentimes takes place long before the sealant reaches the pointof leakage within the well. The well pipe, equipment in the wells andthe like becomes clogged by such a procedure.

An important object of the present invention is to provide a method forlocating leaks in a well pipe and repairing such leaks in situ.

Another object of the present invention is to provide a method oftesting for leaks and repairing such leaks if located, the methodcontemplating positioning a sealant adjacent the area being tested and,if a leak is determined, releasing the sealant and applying the sealantunder pressure to repair the leak in the well pipe.

Still another object of the present invention is to provide a method oftesting a well pipe for leaks and if a leak is located, mixing a plasticsealant material with a catalyst at the location of the leak andapplying the same to the well pipe under pressure.

A further object of the present invention is to provide a method forrepairing leaks in well pipe utilizing a capsule filled with a batch ofsealant and lowered into the well pipe to a point adjacent the leak, thecapsule then being ruptured and the sealant therein applied underpressure to the leak. Ancillary to the preceding, it is a 3,194,310Patented July 13, 1965 further object of the invention to utilize acapsule having separate compartments, one compartment being filled witha plastic sealant material and the other compartment being filled with asuitable catalyst, the capsule being ruptured or fractured at thelocation of a leak and causing mixture of the catalyst and the sealantmaterial in the immediate area with the mixture being applied to theleak under pressure.

Throughout the specification, the term well pipe will be used, and it isintended to cover either a casing in a well bore or a string of flowtubing positioned within the casing. In drilling a well, the walls ofthe bore or hole are supported by what is commonly referred to ascasing. The tubular casing, which comes in long sections, is loweredinto the well after the well hole has been drilled, the sections of thecasing being coupled together in the usual manner by a welded orthreaded joint. The flow tubing is inserted within the casing after thecasing has been inserted into the well bore. When the apparatus is usedin testing flow tubing, the flow tubing remains in situ Within thecasing. On the other hand, when the apparatus is used to test casingsfor leaks, it will be understood that the flow tubing will have beeneither not inserted therein or removed from the casing to permit theinsertion of the apparatus into the casing.

Although the apparatus is primarily intended to test and repair wellpipe while the well pipe is within the well bore, it will be appreciatedthat the apparatus could be utilized to test well pipe removed from thebore and positioned in the derrick. However, the method of the inventionis primarily intended for use in testing well pipe for leaks andrepairing any leaks located in the well pipe while the well pipe remainsin situ within the bore of a well.

These and other objects and advantages of the present invention willappear more fully in the following specification, claims and drawings inwhich:

FIGURE 1 is a vertical section partly in elevation of the apparatusbeing inserted down into a well pipe;

FIGURE 2 is a vertical sectional view similar to FIG- URE 1 butillustrating the apparatus positioned at a desired location within thewell pipe, the spaced barriers of the apparatus being set by fiuidpressure and the apparatus ready for application of fluid under ameasurable pressure to the space between the barriers;

FIGURE 3 is a view similar to FIGURE 2 but showing an additionalsequence in performing the method of the present invention after thetesting of a section of well pipe has been accomplished and prior tofixing or repairing a leak located in the section;

FIGURE 4 is a further vertical section similar to FIG- URE 3 but showingthe apparatus being utilized to repair the leak located;

FIGURE 5 is a schematic view of the apparatus of FIGURES 1, 2, 3 and 4and showing the apparatus sus pended in a well just prior to therepairing of a leak lo cated in the well pipe;

FIGURE 6 is a vertical sectional view through an apparatus similar tothe apparatus of FIGURES 1 through 5 but illustrating a modified meansfor holding the frangible capsule filled with sealant and a modifiedmeans for fracturing such capsule;

FIGURE 7 is a vertical sectional view of a still further modification ofthe present invention. and illustrating a further modified means forfracturing the capsule having the sealant;

FIGURE 8 is a vertical sectional view of the apparatus of FIGURE 7 andillustrating the actuation of the means for fracturing or rupturing thecapsule.

Referring now to the drawings wherein like character and referencenumerals represent like or similar parts, the

apparatus of the present invention as illustrated in FIG- URES 1 through5 is generally designated by numeral 10. As shown in FIGURES 1 through4, the apparatus is illustrated positioned in a well pipe 12 which maybe casing for a well hole or flow tubing inserted within the casing. Itwill be understood that in the example illustrated, the well pipe 12 ismade up of a series of strands or sections 14 and 16 coupled together bya threaded collar 18. The illustrative example discloses the testing ofthe threaded joint between the two stands, but it will be appreciatedthat the apparatus is also used to test the walls of the standsintermediate the collars coupling the stands together.

The improved method of testing the well pipe for leaks and/or repairingthe well pipe for leaks in situ is best understood by referring toFIGURES 1 through 5. For the present, it will suiiice to say that thetesting apparatus 10 is provided with an upper resilient packer element20 and a lower resilient packer element 22 which are spaced from eachother and which are adapted to be expanded into sealing engagement withthe interior of the well pipe by the application of fluid underpressure.

After the packer elements 20 and 22 have been set to form spacedbarriers within the well pipe 12, testing fluid such as water or thelike is flowed into the area between the spaced barriers and ameasurable pressure is applied thereto. Observation of a pressure gaugeG (FIGURE 5), which measures the pressure on the liquid between thebarriers, will determine if there is a leak in the section of pipebetween the barriers. If there is an appreciable drop from the pressureas indicated by the gauge G, then there is a leak. If the test indicatesa leak, the pressure on the fluid between the barriers is relieved andthe barriers are released so that any liquid trapped therebetween candrop by gravity into the well. Then the barriers are reset and afrangible capsule C having a batch of sealant therein and supported inthe area of the leak is fractured and the sealant is flowed into thespace between the barriers. Fluid pressure is applied to the sealant toinject the same into the leaks, the fluid pressure being either water,salt water, barium impregnated mud, drilling mud, or the like. Once thesealant has been injected into the leak and has set, the barriers arereleased and the apparatus is moved to another position within the wellpipe and the test sequence is repeated. A more detailed explanation ofthe method involved in the present invention will appear later in thespecification together with the description of the apparatus.

The apparatus 10 of FIGURES 1 through 5 inclusive includes a pump P(FIGURE 5) suitably supported on the floor of a well derrick or the like(not shown), a source of supply S of liquid such as water, a flexibleconduit 24 connecting the pump P and the source of supply S to anelongated body structure 26. The elongated body structure 26 has amaximum diameter less than the inside diameter of the well pipe 12 andis adapted to support the packer elements 20 and 22. Packer elements 20and 22 are resilient and are adapted to be expanded into engagement withthe well pipe 12. The resilient packer elements 20 and 22 are usuallymade from elastomeric material such as rubber, synthetic rubber or thelike and may be of the type as shown in the drawings which arecompressed longitudinally so that they expand transversely into sealingengagement with the Wall of the well pipe 12 or they may be of the typewhich are provided with an internal cavity and can be inflated.

In more detail, the elongated body structure 26 is provided with acylindrical center portion 28, intermediate portions 30 of reduceddiameter and upper and lower elongated end portions 32 and 34,respectively, of still further reduced diameter. The lower end portion34 is threaded as indicated at 36 and is adapted to receive a roundednose member 38 and a packer retaining nut or back-up ring 40 which abutsagainst one end of the lower packer element 22. A cylindrical cup-shapedpiston 42 is provided on the lower end portion 34 and abuts the packerelement 22 on its end opposite to the end abutting the retaining nut 40.The cup-shaped piston 42 is provided with a cylindrical skirt 44 whichis adapted to slide on the lower intermediate portion 30. It will now beunderstood that when the piston 42 moves downwardly from the positionshown in FIGURE 1 against the packer element 22, it will compress theresilient packer element against the nut or back-up ring 40 and expandthe same transversely into engagement with the well pipe 12 as shown inFIGURE 2.

The upper packer element 20 is mounted on the upper elongated endportion 32 in a similar manner between the back-up ring or retaining nut46 and cylindrical cupshaped piston 48. Movement of the piston 48 towardthe retaining nut 46 compresses the packer element 20 and expands thesame transversely into sealing engagement with the well pipe 12.

The construction and operation of the pistons 42 and 48 and the packerelements 22 and 20 respectively is substantially identical with thatdisclosed in my previously issued United States Patent 2,841,007, July1, 1958, but it will be appreciated that the exact form of the packerelements and the use of fluid pressure to set the same may be inaccordance with the teachings of my United States Patent 2,807,955,issued Octoberl, 1957.

The upper elongated end portion 32 is provided with an open endedenlarged bore 50 which extends axially thereof and which communicateswith a passage 52 extending through the body structure and opening onthe surface of the center portion 28 as indicated at 54. An O-ring seal56 is provided in the shoulder bottom 58 of bore 50. Also, it will benoted that the body structure 26 is made in at least two parts andthreaded together as indicated at 60 in order that an enlarged chamber62 can be provided in the passage 52. The chamber 62 is adapted tosupport the frangible capsule C which houses the batch of sealant aswill be described in more detail later in the specification.

The elongated upper end portion 32 is provided with a passage 64 whichextends therethrough and through the intermediate portions 30, centerportion 28 and lower end portion 34 and opens at 66 and 68 beneath theheads of piston 48 and 42, respectively. The passage 64 where it passesthrough the upper end portion 32 is spaced radially outwardly of thebore 50 and passage 52. The passage 64 has an inlet 70 in the end of theend portion 64. As clearly shown in FIGURE 1, the flexible conduit 24 isthreaded onto the end of the upper elongated end portion 32, asindicated at 72, and thus the body structure can be raised and loweredwithin the well tube.

When liquid from the source of supply S (FIGURE 5) is supplied throughthe pump P into the conduit 24 and into the bore 50, the liquid willflow downwardly through the passage 52 in the body structure 26 aroundthe capsule C in the chamber 62 and out of the outlet 54 into the well.The liquid will also flow into the inlet 70 of passage 64 but since thepressure cannot build up in this passage as passage 52 is continuouslyopen, the pistons 48 and 42 are not actuated. When the apparatus isfirst lowered into the well and liquid is flowed through the conduit 24as described above, the liquid passes from the outlet 54 into the wellpipe past the packers 20 and 22 and, thus, washes away or cleans out anycongealed Weighting material, mud or the like in the well pipe 12. Theapparatus may then be conveniently lowered through the well pipe untilit has reached a desired depth.

After the apparatus 10 has been positioned in the well pipe 12 as fardown as desired, it is then ready for performing a test to determine ifthe well pipe at that position leaks and if such a leak is determined itthen can be utilized to repair such a leak.

Referring now to FIGURE 2, the apparatus of FIG- URE 1 is shown ready toconduct a test on the section of well pipe. In more detail, after thecleansing and lowering action is accomplished as described with respectto FIGURE 1, the pump P is stopped and the liquid within the conduit 24and in the body structure 28 will drain therefrom. The conduit 24 istemporarily disconnected from the pump P in any suitable manner and apressure responsive valve assembly 79 is dropped down the conduit andfits into the bore 50 seating against the O-ring 56. The pressureresponsive valve assembly 79 includes a body portion 80 having a beveledlower end or seat 82 and an elongated stem 84 extending from its upperend. The stem 84 is provided with an enlarged head 86 capable ofreceiving suitable overshot grapples 88 (FIGURE 3). A passage 90 extendsthrough the stem 84 and body 80 and has its lower end communicating withthe upper end of the passage 52. Housed within the body 80 is a pressureresponsive valve 92 including a ball 94 urged against a seat 96 by aspring 98 and a follower 100.

With the pressure responsive valve assembly 79 in the position shown inFIGURE 2, the conduit 24 is again connected to the pump P and the pumpis operated to supply liquid under pressure through the conduit 24 tothe body structure 26. The ball 94 closes the passage 90 and,consequently, the liquid will first flow through the inlet 74 into thepassage 64 at a sufficient pressure to urge the pistons 48 and 42 inopposite directions to thereby set the packers 20 and 22 respectively.Once the pressure in the passage 64 has caused the packer elements 20and 22 to be set and form spaced barriers in the well pipe 12, thepressure of the liquid in the pipe 24 is increased. When the pressure ofthe liquid has increased sufiiciently to unseat the ball 94 from itsseat 96, the liquid will flow through the passage 90, passage 52 and outof the outlet 54 between the packer elements. The gauge G, providedadjacent the pump P can be observed as the pressure of the liquidbetween the packer elements 20 and 22 is built up to a predeterminedamount. Once the pressure of the liquid has reached the predeterminedamount, the gauge is observed for an appreciable drop in pressure and,if such a drop occurs, it will indicate that the section of well pipebeing tested has a leak therein.

If the operator notes that there is a leak, the pressure of the liquidflowing into the conduit 24 is relieved and thus the ball 94 will seatand the pistons 48 and 42 retract so that any liquid trapped between thebarriers can drop by gravity down the well pipe.

Referring now to FIGURE 3, the conduit 24 is again disconnected and theovershot grapple 88 which includes the spring tongs 102 is lowered intothe conduit 24 until it engages the enlarged head 86 of the pressureresponsive valve assembly 79. The valve assembly 79 is removed from thebore 50 and any liquid trapped in the passages 52 will flow by gravitytherefrom out of the outlet 54 past the lower packer element 22. WhileFIG- URE 3 shows the packer elements expanded, it will be appreciatedthat before the pressure responsive valve assembly 79 is removed, thepacker elements will have become relaxed due to the removal of pressurefrom the liquid in the conduit 24. If for any reason there is fluidtrapped between the packer elements which would tend to maintain thepacker elements in sealing engagement, removal of the pressureresponsive valve assembly 79 will cause an equalization of pressure onthe fluid between the packer elements and the pressure beneath thepistons 48 and 42, thus causing an immediate full relaxing of the packerelements so that the liquid can drop into the well.

After the pressure responsive valve assembly has been removed, theapparatus will again assume the relaxed position shown in FIGURE 1. Asecond conduit 110 having a tubular member 114 threaded thereon, asindicated at 116, is then lowered within the conduit 24 until the lowerbeveled end 118 of the tubular member 114 seats against the O-ring 58 inthe bottom of the bore 50.

The tubular member 114 is provided with an enlarged bore 120communicating with a reduced bore 122 at its lower end. A lance element124 having a piston head 126 slidable in the bore 120 is adapted toextend through the bore 122 and the passageway 52 in the body structure26. A by-pass passage 128 is provided between the bore 120 and thepassage 122 so that liquid can flow past the piston head 126 through thepassage 52 when the piston head is in the position shown in FIGURE 4.

When the conduit 110 with a tubular member 114 and its lance element 124have been lowered within the conduit 24, the upper end of the conduit110 is connected to a pipe 130 leading from a pump P suitably supportedon the floor of the derrick. The pump P is connected to a source ofsupply S which may be water, salt water, drilling mud, or bariumimpregnated mud.

With the apparatus connected as shown in FIGURE 4 but with the lanceelement 124 positioned vertically upwardly in the bore 120, the conduit24 is reconnected to the pump P which is then started so as to flowwater under pressure down the conduit 24 into the passage 64 and thisactuates the pistons 48 and 42 to reset the packer elements 20 and 22respectively. Once the packer elements have been reset, then the pump Pis actuated to cause flow of fluid in the conduit 110. The pressure ofthe fluid acting on the piston head 126 of the lance element 124 drivesthe same downwardly to a position where it penetrates the capsule C.Continued application of pressure on the head 126 will move the head tothe position shown in FIGURE 4 and then the liquid in the bore canby-pass around the head through the by-pass passage 128 into the passage52 and thus force the sealant out of the fractured capsule C and injectthe same into the leak in the well pipe. As soon as it is determinedthat the sealant has been injected into the leak in the well pipe, thepressure can be relieved on the packers 20 and 22 and in the conduit 110so that the conduit 110 may be raised upwardly so as to remove thetubular member 114 from the seat 58. After the pressure has beenrelieved on the packers 20 and 22, water may be flowed through theconduit 24 to clean out the passages 52, chamber 62 and the bodystructure 26 may then be raised so that a new capsule may be positionedin the chamber and the tests repeated at dilferent portions along thewell pipe until such time as another leak is located. The testing and/or repairing operation will then be repeated as described above.

The capsule C shown in FIGURES 1 to 4 is made of a frangible materialsuch as hard vulcanized rubber, ceramic, or any molded plastics such asBakelite. And it has compartments A and B in which a plastic sealantmaterial and a catalyst are segregated from one another until time ofuse. Also, the capsule C may be constructed of a metal case withfrangible ends and/or partitions to separate the plastic sealant fromthe catalyst. Preferably the capsule is made from a material which willshatter upon contact by the lance element 124 so that the catalyst andthe plastic sealant material will quickly mix. The type of plasticsealant used depends upon the existing downwell conditions such as themagnitude of the leak, well temperature and well pressure at the site ofleak, type of fluid being produced through the tubing, type of fluidcontained in the space around the pipe such as mud and water, or thelike. Plastic sealants which have been used are cellulose esters, e.g.,cellulose acetate butyrate; polyurethane resins, e.g., from toluenediisocyanate and polypropylene glycol molecular weight 2025, orpolyphenylene polyisocyanate (PAPI) and the polyester of adipic acidwith diethylene glycol and trimethylol propane; and any of the phenolicresins such as phenolformaldehyde, cresol formaldehyde andphenol-furfural; epoxies, e.g., bisphenol A-epichlorhydrin resin;silicones, e.g., polydimethyl siloxane; and acrylates, e.g., polymerizedmethyl methacrylate and polymerized ethylacrylate. The catalysts useddepend upon the particular sealant used. With cellulose acetate butyrateand phenolics, an

acid type of catalyst such as hydrochloric acid or sulfuric acid isused. On the other hand, in addition to acid catalysts, an amine complexcatalyst, e.g., boron-fluoridetriethyl amine can be used with theexpoxies whereas a peroxide catalyst, e.g., benzoyl peroxide or cumenehydroperoxide is used with the acrylates. Fillers, such as wood flour,metallic powder, asbestos fiber, glass fiber, alpha cellulose, lignin,or cellophane shreds may be carried with the sealants.

FIGURE 6 illustrates a modified form of apparatus capable ofaccomplishing the method of the present invention. In the apparatus ofFIGURE 6, the body structure 26 is substantially identical to the bodystructure 26 previously described in that it is provided with upper andlower packer elements 20 and 22 expansible by actuation of the pistons48 and 42 respectively. However, the body structure 26 is not providedwith an enlarged chamber for housing the capsule C. In the modificationin FIGURE 6, after the test has been made on the section of well pipeand it has been determined that the same leaks, the pressure responsivevalve assembly 79 of FIGURE 3 is removed from the bore 50 as previouslydescribed and a tubular member 200 is attached to its lower end. Thetubular member 200 is provided with a passageway 202 which extends intoan enlarged chamber 204 that houses a piercing or lance element 206having a piston head 210. The enlarged chamber 204 also houses beneaththe lance element 206 the frangible capsule C. A by-pass passage 212 isprovided at the lower end of the enlarged chamber 204 and extends to areduced opening outlet 214 of the chamber 204.

In the modification shown in FIGURE 6, it is not necessary to run aseparate conduit into the conduit 24 in order to actuate the lanceelement 206. Once the tubular member with the lance element 204 andcapsule C has been positioned as shown in FIGURE 6, the pump P isstarted and liquid is flowed down the conduit 24. The pressureresponsive valve assembly 79 initially prevents actuation of the lanceelement 206 but allows the liquid to flow in the conduit 64 so as toactuate the pistons 48 and 42 to expand the packer elements 20 and 22.Upon setting of the packer elements 20 and 22, pressure builds up in theconduit 24 and eventually forces the pressure responsive valve element94 off of its seat so that liquid can flow through the passage 202against the head of piston 210 to force the lance element 206 downwardlywhere it fractures the capsule C. Continued downward movement of thepiston element completely crushes the capsule and when the piston 210passes the by-pass 212, liquid flowing in the conduit 24 can by-passthrough the passage 212 out of the opening 214 to force the mixture ofsealant material and catalyst through the passage 52' out of the opening54 and inject the same under pressure in the leak in the well pipe 12.Once the leak has been repaired, the pressure responsive valve assembly79 with the attached tubular member 200 is removed from the conduit 24by the overshot grapple 88 and the system is then flushed with thepackers relaxed, as shown in FIG- URE 1.

FIGURES 7 and 8 illustrate a further modification of the presentinvention and, more particularly, a modification to the means forfracturing or rupturing the capsule C. In FIGURE 7 the body structure26" is identical with the body structure 26 with the exception that itis provided with a vertical bore 220 which extends downwardly from thechamber 62 and out of the lower end portion 34. The bore 220 has aportion of its length threaded, as indicated at 222, and is adapted toreceive a threaded stem 224 of the lance element 226. The portion of thestem 224 which extends outwardly of the lower end portion 34 is providedwith a drag spring assembly 228 having springs 230 which frictionallyengage the side walls of the well pipe 12. After a leak has been locatedby operation of the apparatus 10" in a similar manner as described withrespect to FIGURES 1, 2 and 3, the

packer elements 20 and 22 are released as shown in FIGURE 7 and theconduit 24 is disconnected from the pump. Then the conduit 24 is rotatedso as to rotate the body structure 26" relative to the threaded stem224. This will cause the threaded stem to elevate the lance element 226so that it penetrates and fractures the capsule C. As soon as thecapsule has been penetrated, the pressure responsive valve assembly 79is again lowered into the bore 50 and the conduit 24 is again connectedto the pump P and liquid is flowed through the conduit to cause initialsetting of the packer elements 20 and 22, as shown in FIGURE 8. Aftersetting of the packer elements 20 and 22, the liquid pressure isincreased to unseat the valve 94 so that liquid can flow through thepassage 52 into the chamber 62 to force the plastic sealant material andcatalyst mixture out of the opening 54 and into the leaks in the wellpipe. After the leak has been repaired, the pressure responsive valve 79may be fished out of the conduit 24 and water may be flowed through thebody structure 26" to thereby flush out the inside mechanism of theapparatus and thus prevent any sealant left therein from foulingsubsequent operation.

While the method and the apparatus described above fully accomplish theobjects and advantages of the present invention, it is, of course,within the scope of the present invention that certain changes andmodifications may be made without departing from the spirit of theinvention. Therefore, the terminology used in this specification is forthe purpose of description and not for limitation, as the scope of theinvention is defined in the claims.

What is claimed is:

1. A method of testing a well pipe in a well for leaks and repairing thesame IILSitl1 if any leaks are determined by the test comprising thesteps of: establishing spaced barriers within the well pipe on eitherside of a section to be tested; positioning a frangible capsule filledwith a sealant within the pipe adjacent the section being tested;applying a measurabhe pressure to the section of well pipe between thespaced barriers while said capsule is being maintained in the positionadjacent the section being tested, and observing for a drop i n pressuredue to a leak in the pipe; releasingthe pressure between the barriers;fracturing the capsule to release the sealant if the test indicates aleak in the well pipe; and then applyingka pressure to the sealant toforce the same into the 2. A method of testing a well pipe in a well forleaks and repairing the same in situ if any leaks are determined by thetest comprising the steps of utilizing a fluid under pressure toestablish spaced barriers within the well pipe on either side of asection to be tested; positioning a frangible capsule filled with asealant within the pipe adjacent the section being tested; flowing aliquid into the space between the barriers and applying a measurablepressure to the same while maintaining said capsule in the positionadjacent the section being tested, observing fora drop in pressure dueto a leak in the pipe; releasing the pressure on the liquid between thebarriers and releasing barriers so that the liquid drops by gravity intothe well; reestablishing the barriers if a leak has been determined andthen fracturing the capsule to release the sealant between the barriers;and then applying a pressure to the sealant to force the same into theleak.

3. A method of repairing a leak in a section well pipe while the wellpipe remains in situ within the well comprising the steps of:establishing spaced barriers within the well pipe on either side of thesection well pipe, and at the same time positioning a frangible capsulewithin the well pipe adjacent the section, the frangible capsulecontaining a sealant; fracturing the capsule and flowing the sealantinto the space between the barriers, and applying pressure on thesealant to force the same into the leak in the section of well pipe.

(References on following page) References Cited by the Examiner UNITEDSTATES PATENTS Beecher 166-4 McLennan 166-14 X Kerman 166-14 Smith166-14 Wrightsman 166-33 Dyer 166-32 X 1 10 Jennings 166-33 X Holland eta1. 166-33 ONeal 166-14 X Bernard 166-33 Bearden et a1. 166-29 Lebourg166-21 CHARLES E. OCONNELL, Primary Examiner.

Davis et al 166 33 X 10 BENJAMIN HERSH, Examiner.

3. A METHOD OF REPAIRING A LEAK IN A SECTION WELL PIPE WHILE THE WELLPIPE REMAINS IN SITU WITHIN THE WELL COMPRISING THE STEPS OF:ESTABLISHING SPACED BARRIERS WITHIN THE WELL PIPE ON EITHER SIDE OF THESECTION WELL PIPE, AND AT THE SAME TIME POSITIONING A FRANGIBLE CAPSULEWITHIN THE WELL PIPE ADJACENT THE SECTION, THE FRANGIBLE CAPSULECONTAINING A SEALANT; FRACTURING THE CAPSULE AND FLOWING THE SEALANTINTO THE SPACE BETWEEN THE BARRIERS, AND APPLYING PRESSURE ON THESEALANT TO FORCE THE SAME INTO THE LEAK IN THE SECTION OF WELL PIPE.